Anthocyanins are water soluble pigments which are responsible for the attractive colors of many flowers, fruit and leaves. Generally, they can be extracted from plants by acidified alcoholic solvents and many are available commercially as food colorants. They are often supplied with malto dextrin as a diluent in a concentration suitable for inclusion in beverages or other foods such as cereals.
Anthocyanidines, the aglyconic component of anthocyanins, have a basic structure as shown in Formula I.

Typical examples are: cyanidin (hydroxylated at positions 3, 5, 7, 3′, 4′), delphinidin (hydroxylated at positions 3, 5, 7, 4′, 5′) and pelargonidin (hydroxylated at positions 3, 5, 7, 3′). The hydroxyl groups are usually glycosylated (e.g., an anthocyanin) and/or methoxylated (e.g. malvidin is substituted at the 3′ and 5′ hydroxyl groups and paeonidin and petunidin are substituted at the 3′ hydroxyl group).
Anthocyanins are water-soluble glycosides of polyhydroxyl and polymethoxyl derivatives of 2-phenylbenzopyrylium or flavylium salts. Individual anthocyanins differ in the number of hydroxyl groups present in the molecule, the degree of methylation of these hydroxyl groups, the nature, number and location of sugars attached to the molecule and the number and the nature of aliphatic or aromatic acids attached to the sugars in the molecule. Hundreds of anthocyanins have been isolated and chemically characterized by spectrometric tools. Cyanidins and their derivatives are the most common anthocyanins present in vegetables, fruits and flowers.
Anthocyanins share a basic carbon skeleton in which hydrogen, hydroxyl or methoxyl groups can be found in six different positions as noted above. In fruits and vegetables, six basic anthocyanin compounds predominate, differing both in the number of hydroxyl groups present on the carbon ring and in the degree of methylation of these hydroxyl groups. The identity, number and position of the sugars attached to the carbon skeleton are also variable; the most common sugars that can be linked to carbon-3, carbon-5 and, sometimes, carbon-7, are glucose, arabinose, rhamnose or galactose. On this basis, it is possible to distinguish monosides, biosides and triosides.
Another important variable that contributes to the chemical structure of anthocyanins is the acylating acid that can be present on the carbohydrate moiety. The most frequent acylating agents are caffeic, ferulic, sinapic and p-coumaric acids, although aliphatic acids such as acetic, malic, malonic, oxalic and succinic acids can also occur. Up to three acylating acids can be present simultaneously.
Due to their particular chemical structure, anthocyanins and anthocyanidins are characterized by an electron deficiency, which makes them very reactive toward reactive oxygen species (ROS), also known as free radicals; they are consequently considered to be powerful natural antioxidants.
Anthocyanins, due in part to the nature of their chemical structure, tend to be unstable and susceptible to degradation. Additionally, the stability of anthocyanins is effected by pH, storage over a period of months, storage temperature, presence of enzymes, light, oxygen, and the presence of proteins, flavonoids and minerals
More particularly, the bioavailability of anthocyanins is low due to their sensitivity to changes in pH. Anthocyanins are generally stable at pH values of 3.5 and below, and are therefore stable under stomach conditions. However, they degrade at higher pH values, such as those more typical for the intestinal tract (pH of 7) and thus beneficial absorption and nutritional value is greatly reduced.
Therefore, a need exists for a composition and/or method that provides stabilized anthocyanins.